Many of us store lily material in small dedicated unites. Thermometers should always be suspect for poor accuracy--All you have to do is check several of the same type hanging on the store rack. I recently checked eleven, hanging one behind the other in a big box store and the temperature ranged from 67'F to 79'F. Disgusting! And don't expect those digital units with remote sensors to do much better. They may show better agreement for unit to unit in the store at 72'F but take them home and see what you read at 32'F. The unit in my greenhouse runs 5.7'F low at 32'F actual on one sensor and 3.2'F low on the other sensor.

Truth is--no thermometer made, not even expensive Laboratory thermometers are 100% accurate throughout a wide temperature range. But we really DO need to know what our lily fridges are running at, right? Well, turns out one of the most accurate thermometers you can use, ends up being a cheap 'generic' dial type ( doesn't matter who's name is on it)--if your willing to do an interesting little experiment and make a tiny, simple adjustment. Follow me.

Dial Thermometer has adjustment nut at stem top. It can be losened slightly and the dial head can be rotated to exact temp. desired, then snugged back tight.

Edit: SPECIAL NOTE ADDED. For most precise calibration, I recommend using distilled or pure water. Certain well waters may contain harmless low levels of minerals like calcium, copper ions, etc. which could slighty lower the actual freezing point of the solution. Municipal water may also have other additive that have a similar affect.



Next I placed a glass beaker ( a 12 oz glass will do, too) of water and dial thermometers outside early in the morning when the temp. is 20'F or colder and I placed it outside a sliding door where I could keep an eye on it from inside, checking periodically for the sight of ice crystals. And I faced the dials toward ith inside so I could watch the temp. drop, also.



You can watch the ice crystals as they form in three dimensional--very beautifull. Some as long as needles, others like crystal chandeliers suspended in space. The entire contents will now stay at 32'F until it all frrezes so I've got enough time to make the adjustment and recheck to verify. These thermometers checked 3' and 5' high at 32'F




And and the now both read 32'F. Easy adjustment--got both correct the first time! Kinda fun!



Now I have a beaker with water a calibrated thermometer which I'll set in my fridge overnite and check in the morning; in fact, I'll check all four corners and the freezer section too. Finally, peace of mind!

Interesting! And what temp do you store your lilies at?

I like the beaker with the handle... looks like one of those promotional things.

Polly, the little baby bulbs I chill inside over winter are stored at 34-35'F in two dedicated small refrigerators with freezer compartments for seeds, 0' to 5'F for seeds and pollen. Likewise for mature bulbs that I hold a few days for planting ( 34-35'F). Baby bulbs overwintered outside in tipped pots are allowed to go no lower than 28'F. I monitor that temp with a much longer soil/compost dial thermometer that I insert down into a vertical half inch PVC tubing that I have preinstalled into the soil at storing time. Works great!

Connie, I've still got a bunch of beakers around from my younger days in the lab fresh out of school. But this particular one with the handle I picked up at a Goodwill type store a couple years ago. Handy for mixing liquid fertilizer,etc. Say, the pictures I just posted in the 'lily seed thread' are of some you sent.

Lorn, I worked in an analytical lab where we would get freebies from vendors and one of my favorites were these beakers that had handles added to them and they were intended for use as coffee cups. One day the safety committee came along and accused us of drinking out of labware (big no no). Henceforth we had to do our drinking surreptitiously, having a preplanned place to stuff it if someone came along. I'm not talking about drinking in the lab but in our offices!

Glad to hear some of my seeds are still coming along. I haven't been on the forum much lately though I check it out daily. Right now I am not happy with my seedlings as they somehow became infected with aphids and their whole life has been in the house under lights. I have now put them out on the front porch for the winter. Not sure what to do about the problem and it probably won't get cold enough here to kill them off. Of course they are on the BOTTOM sides of the leaves; hard to get at without snapping the leaves off .

I like the idea of calibrating thermometers. Right now I don't have a dial type adjustable thermometer to use for calibration. Need to pick one up.

And I almost asked you about calibrating when you mentioned it on the other thread. Thanks for this,m Lorn.

What kind of water are you using? It would be interesting to see if pure (or closer to pure) distilled water acts any differently.

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Is 28 F a "magic" number for baby bulbs that you gleaned from somewhere, or a parameter you decided upon based on your theory/ experiments/reading?

More power to ya, Lorn, but I'm just not that fastidious. ....not that there is anything wrong with that (cue that Seinefeld episode ). All my potted lilies that winter outside, babies and adults alike, are exposed to at least 10 degrees below that. Of course, anything in active growth would be given special attention.

There's room for more temperature divergence in refrigerator storage. My only fridge is kept as cold as I dare. Stuff stored in the back often freezes, especially when things are packed. This is my preferred area for most any live material I overwinter in the fridge. My reasoning stems from the growth patterns of pathogens and hosts. In the case of lilies, when bulbs are at rest, say at 35 F, so is its immune system. They don't have the ability to attempt to fight off pathogen (disease) attacks. But pathogens (in general) do not rest at lower temperatures, they just grow more slowly. Thus, infections grow unchecked. However, at lower temps, say 30-31 F or lower, all growth is essentially stifled.

Connie, there's a product by S C Johnson Co. (Johnson Wax) that you might try. It's called Raid 'House and Garden'. It comes in an aerosol can and is safe for indoor plants and indoor use.. However, when it comes to my little seedlings, I'm very skeptical about using anything--that's why I was so curious about the cinnimon concept. I have used this only once in a daring move on a single pot of seedlings for a tiny little knat type flying insect that inhabited the pot. It worked, but I still don't have enough user knowledge of it with lilies. Says it kills aphids--spray/fog from a distance of 2 feet.

Rick, the 28'F is the lowest number I have experience with for burried seedling pots. Anything lower would be unexplored territory for me. I guess you're saying that they could go quite a bit lower and I think so too, but I just never got that low. I know fully mature bulbs must be able to go a lot lower. A couple years ago, some extra LAs inadvertantly got stacked in the bottom of some empty pots I had stacked up and stored outside behind the garden shed all winter long and when my grandaughter planted them--they flowered the same year.

I used my regular well water for the calibration excersize--which is pretty soft. It's ironic, but I just didn't have any of either distilled or pure water here at the time--something I usually always have plenty of. So my readings are now maybe just a tad deceptively higher than the actual freezing point. Agreed--it would be interesting to see just 'how much' difference--I suspect probably only a couple tenths.. So, we'll do another with these same two thermo's next cold morning I get. I went back and edited in a SPECIAL NOTE to my original post to recommend distilled or pure water for most accurate results. Good Point.

To be honest, I really hadn't thought much about pathogens--other than slowing them down, down, down. But your thinking is better (two heads are better than one). I'm going to lower my temps down to as you say 30- 31'F. Good thought--good tip!

I am not sure if purified water counts as close to pure water in the sense that it is just H20. I just don't know. What will make the difference is what compound is in solution (some lower melting points, some may not) and the degree of concentration.

A little off topic, but my mention of the pathogen/host relationship in regard to temperature stems from observations interpreted several decades ago by Alex Shigo, biologist and plant pathologist. His work questioned the long standing "rule" that pruning trees is best during the dormant season. Pertinent to our discussion, he observed canker disease wounds on tree trunks and branches. During the growing season, the tree would fight the disease, via production of compartmentalizing tissues, callusing, etc., and often gain the upper hand. But when the tree goes dormant, all that stops. However, the canker disease continues to proliferate and invade the tree. When the next growing season starts, the tree is often back to square one, or worse.

Sometimes juvenile stages of plants are actually more cold hardy than adults. Sometimes less cold hardy. I am not sure how this applies to lilies, but it is a concept to keep in mind. In the case of bulbs and corms (lilies, tulips, daffodil, gladiolus, etc.), one would think that the natural inheritance would be that young bulbs would be more cold hardy, since they would naturally be nearer to the soil surface in early years, and more vulnerable to extreme temperature swings. Once again, this is only educated conjecture.

Connie, have you been trying the bowl of vinegar with the saran wrap on top and holes poked in? I think we talked about that last year.

Thanks Lorne. I have on occasion received shipment of bulbs mid winter, and kept them right at 31.

A lot of scientific stuff going on here

Hi Polly, yes I did try that, both under my lights and out in the greenhouse. Results were mixed... a few gnats/whiteflies wandered into the traps but I think the yellow sticky strips were more effective. I don't know how it might work with aphids since I just recently discovered them. I didn't even know I had them since they hide on the underside of the leaves. They must have come in on some other plant that I bought and put under the lights. I just wish the foliage would die back so I can clean it all up. But living in a little banana belt here that may not happen at all for some of my seedlings.

I like all that science stuff too .